在现场化泡泡测量揭示了 bryophytes 中缺乏光激活的护卫细胞度调节
Craig R Brodersen1, Tim J Brodribb2, Uri Hochberg3
1School of the Environment, Yale University, New Haven, CT 06511.
概括
植物缺乏动态的护卫细胞流控制,与血管植物不同. 这表明早期的陆地植物可能没有调节光合作用和干燥预防的口腔功能.
科学领域:
- 植物生理学 植物生理学
- 进化生物学 进化生物学
- 生物物理学的生物物理.
背景情况:
- 植物口腔功能在4亿多年前随着大气变化而演变.
- 布里奥菲特的口腔解剖学与早期的陆地植物相似,为口腔进化提供了潜在的见解.
- 测量现场卫细胞压的技术挑战使得我们对植物口腔行为的理解有限.
研究的目的:
- 引入和验证一种用于监测完整植物组织中卫细胞压的新方法.
- 为了研究 bryophyte 守护细胞中的依赖光的压调节.
- 为了比较 bryophytes 与血管植物中的流动力学和口腔反应.
主要方法:
- 在护卫细胞内开发了一种微泡核化技术,以测量压.
- 应用了爱斯坦-普莱塞特方程,将微泡动力学与周围流体压力相关联.
- 监测了白植物和血管植物的黑暗与光适应的护卫细胞中的压.
主要成果:
- 在植物守护细胞中没有观察到光激活的压变化;压力与表皮细胞相似.
- 血管植物表现出显著的依赖光的度调节,导致可逆的口腔孔径变化.
- 守护细胞流的丧失并没有影响植物的口腔口,但在血管植物中导致了部分或完全的闭合.
结论:
- 尽管保持了口腔形态,但菌体缺乏动态的护卫细胞流控制.
- 这一发现与血管植物形成鲜明对比,在这些植物中,流调节对于光合作用和干燥抑制至关重要.
- 这项研究强调了早期陆地植物和血管植物之间的口腔调节机制的分歧.
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